Risk factors for hospital-acquired Staphylococcus aureus bacteremia

Arch Intern Med. 1999 Jul 12;159(13):1437-44. doi: 10.1001/archinte.159.13.1437.

Abstract

Background: Staphylococcus aureus bacteremia (SAB) acquired in hospitals continues to be a frequent and serious complication to hospitalization, and no previous case-control studies dealing with risk factors of this severe disease are available.

Methods: Based on a 1-year prospective analysis, the data from all patients with hospital-acquired SAB admitted to 4 hospitals in Copenhagen County, Denmark, from May 1, 1994, through April 30, 1995, were evaluated. Eighty-five patients with hospital-acquired SAB were matched to 85 control patients with a similar primary diagnosis at admission (matched controls). Of these, 62 patients with hospital-acquired SAB were compared with 118 other patients with a similar time of admission, who were randomly selected with no clinical evidence of SAB (unmatched controls).

Results: The incidence of hospital-acquired SAB was 0.71 per 1000 hospital admissions. The presence of a central venous catheter (odds ratio, 6.9; 95% confidence interval [CI], 2.8-17.0), anemia (odds ratio, 3.3; 95% CI, 1.4-7.6), and hyponatremia (odds ratio, 3.3; 95% CI, 1.5-7.0) was significantly associated with hospital-acquired SAB in a conditional and a usual logistic regression analysis. Nasal carriage was not an independent risk factor, but nasal carriers among patients in surgery (odds ratio, 4.0; 95% CI, 1.3-13.0) had a significantly higher risk for hospital-acquired SAB compared with matched and unmatched controls. The presence of hospital-acquired SAB increased the mortality rate 2.4-fold (95% CI, 1.1-5.2).

Conclusions: The presence of a central venous catheter is an important risk factor, and hyponatremia and anemia are associated with the development of hospital-acquired SAB. Furthermore, hospital-acquired SAB in itself increases mortality.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adrenal Cortex Hormones / adverse effects
  • Adult
  • Age Factors
  • Aged
  • Aged, 80 and over
  • Anemia / complications
  • Anti-Bacterial Agents / adverse effects
  • Bacteremia / epidemiology*
  • Bacteremia / etiology*
  • Bacteremia / microbiology
  • Case-Control Studies
  • Catheterization, Central Venous / adverse effects
  • Child
  • Child, Preschool
  • Cross Infection / epidemiology*
  • Cross Infection / etiology*
  • Cross Infection / microbiology
  • Denmark / epidemiology
  • Female
  • Hospitals, Community
  • Humans
  • Hyponatremia / complications
  • Immunocompromised Host
  • Infant
  • Infusions, Intravenous / adverse effects
  • Male
  • Middle Aged
  • Nose / microbiology
  • Odds Ratio
  • Prospective Studies
  • Regression Analysis
  • Renal Dialysis / adverse effects
  • Risk Factors
  • Sex Factors
  • Staphylococcal Infections / epidemiology*
  • Staphylococcal Infections / etiology*
  • Staphylococcal Infections / microbiology
  • Staphylococcus aureus*
  • Surgical Procedures, Operative / adverse effects
  • Survival Analysis
  • Transfusion Reaction

Substances

  • Adrenal Cortex Hormones
  • Anti-Bacterial Agents